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Finding the Fourth Proportional to 30.81, 46.19 and 18.61

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Solution

The fourth proportional to 30.81, 46.19 and 18.61 is: 27.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    30.81 : 46.19 = 18.61 : x
  2. Step 2: Convert to fraction form
    30.81/46.19 = 18.61/x
  3. Step 3: Cross multiply
    30.81x = 46.19 × 18.61
  4. Step 4: Simplify right side
    30.81x = 859.42
  5. Step 5: Solve for x
    x = 859.42/30.81
  6. Step 6: Final answer
    x = 27.90

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.